Semi-automatic gun mount

ABSTRACT

A semi-automatic gun mount allowing an operator to fasten together respective members to form a plurality of lineally spaced joints, characterized by at least one rail, referred to as a monorail, disposed adjacent the location where the lineally spaced joints will be formed; a carriage guidably supported on the monorail with minimal lateral extension; a first means, such as spaced apart wheels gripping the monorail and a vertically disposed rail, for facilitating movement of the carriage longitudinally of the monorail with minimal friction, for retaining the carriage on the monorail with sufficient force to carry a cantilevered gun and for facilitating removal and installation of the carriage and its gun from and onto the monorail; vertically movable support plate on the carriage for supporting the gun; stop for limiting vertical movement of the support plate; and adjustable biasing means yieldingly urging the support plate upwardly into its uppermost position in engagement with the stop. The support plate is movable downwardly by an operator against the force of the adjustable biasing means to position the gun in a plurality of vertically spaced nailing positions adjacent each joint. Also disclosed are specific preferred embodiments.

llnited States Patent [191 Umphressi SEMI-AUTOMATIC GUN MOUNT [76] inventor: Kennith D. Umphress, 2751 Ludell,

Fort Worth, Tex. 76105 22] Filed: 1 May 22,1972

[21 Appl. No.: 255,414

Primary Examiner-Granville Y. Custer, Jr. Attorney, Agent, or Firm-James C. Fails; Wofford, Felsman, Fails & Zobal M 57 ABSTRACT A semi-auto matic'gun mount allowing anoperator to fasten together respective members to form a plurality July 9, 1974 of lineally spaced joints, characterized by at least one rail, referred to as a monorail, disposed adjacent the location where the lineally spaced joints will be formed; a carriage guidably supported on the monorail with minimal lateral extension; a first means, such as spaced apart wheels gripping the monorail and a vertically disposed rail, for facilitating movement of the carriage longitudinally of the monorail with minimal friction, for retaining the carriage on the monorail with sufficient force to carry a cantilevered gun and for facilitating removal and installation of the carriage and its gun from and onto the monorail; vertically movable support plate on the carriage for supporting the gun; stop for limiting vertical movement of the support plate, and adjustable biasing means'yieldingly urging the support plate upwardly into its uppermost position in engagement with the stop. The support plate is movable downwardly by an operator against the force of the adjustable biasing means to position the gun in a plurality of vertically spaced nailing positions adjacent each joint. Also disclosed are specific preferred embodiments.

8 Claims, 3 Drawing Figures I SEMI-AUTOMATIC GUN MOUNT BACKGROUND OF THE INVENTION 1. Field of the Invention I This invention relates to fastening together of members to form joints, such as in the fabrication of building panels or structures. More particularly, it relates to a semi-automatic gun mount for fastening together, as by nailing, prepositioned elements to form a structural frame.

2. Description of the Prior Art For many years there has been an increasing tendency in the building industry to fabricate building sections using assembly line production techniques. The pre-assembled building sections, frames, or panels may be then transported to the job site to form the completed or partially completed structure. For several years now, guns have been carried on carriages that traverse t rack means alongside platforms or the like on which the components of the structural frame have been pre-assembled with joints adjacent the edges. For example, a table, trailer or the like, will have top and bottom plates positioned alongtwo sides with studs therebetween, and a carriage and gun that roll along tracks alongside the platform for nailing the studs to the plates. To prevent rotation of the studs, two nails are driven into each end of each stud, one at the top of each of the plates and one at the bottom of each of the plates, requiring moving the gun vertically to at least two positions. The prior art apparatus has suffered from two major disadvantages on these semi-automatic type gun mounts. The first of these disadvantages is that the carriage was provided on track means comprising horizontally spaced tracks such that a significant additional lateral dimension was provided. The additional lateral dimension made access to the joints for nailing more difficult, with more chances for back injury; and caused problems legally moving a portable platform, or trailer, to a new job site. For example, as much as 14 to 16 inches laterally were added onto each side of a trailer such that, with an 8 foot building panel, the trailer could not be towed legally down the highway to the job site. Moreover, the large lateral dimension created a significant moment arm suspended from the side of the trailer or platform which when multiplied by the track means ultimately carrying the weight of the carriage, support plates and gun created a force couple. The force couple was large enough to cause the track Insofar as I am aware, the prior art has not provided apparatus which obviated these two major disadvantages.

Accordingly, it is an object of this invention to provide a semi-automatic gun mount for use alongside a trailer, platform or the like for fastening joints together that obviates one or more of the major disadvantages of the prior art apparatus.

It is a specific object of this invention to provide a semi-automatic gun mount that obviates both the disadvantages of the prior art apparatus and that provides a semi-automatic gun mount requiring very small lateral extension onto the platform or trailer and that requires only a small amount of force to move the gun downwardly into a second vertical position regardless of whether or not the holder is completely loaded or only partially loaded with fasteners, such as nails.

BRIEF DESCRIPTION OF THE DRAWINGS DESCRIPTION OF PREFERRED EMBODIMENT(S) Referring to 'FIG. I, a plurality of joints, as between respective studs 11 and plates 13, are to be nailed together to form a panel structure, such as a wall panel.

Ordinarily, the components, such as the studs and plates 11 and 1 3, are assembled on a location, such as sembled are on a platform or in a more portable form,

means supports to bend away from the trailer or .break off entirely; particularly when the workman had to press hard downwardly, as described with respect to the second disadvantage.

The second major disadvantage was the use of a constant force means for yieldingly urging the. support plate and the gun upwardly into engagement with the stop with afixed force. When the constant force means, such as a spring, were chosen with sufficient force to hold the loaded gun with a full compliment of fasteners, such as 1,000 nails, in its holder, the operator was required to push down with an increasingly greater force as the nails were used from the holder. Accordingly, the operator became tired more rapidly than necessary; particularly since he had to bend over farther because of lateral extension of the dual horizontally spaced tracks.

such as on a trailer. For purposes of the description hereinafter, the reference will be made to a trailer that may be towed to a job site, since it is in this embodiment that this invention has its greatest advantages. It is to be remembered, however, that this semi-automatic gun mount has a high degree of versatility and is useful in a wide variety of apparatus where a plurality of members forming lineally aligned joints are to be fastened together, as by nailing. At least one rail 17, hereinafter referred to as a monorail, is connected, as by welding,

with the side member 15 in substantially parallel relationship with the linearly aligned joints between the studs 11 and the plate 13. The monorail 17 may be affixed to the side member 15 by bolts or any other suit-. able means. The monorail 17 extends for the length of the side member 15 so as to enable acarriage carrying a gun to traverse the length of the plate 13, nailing all of the studs 11 to the plate 13.

A carriage I9 is guidably supported on the monorail 17 with minimal lateral extension being required, even with the carriage attached. With the carriage removed from the monorail 17 there is no substantial lateral extensionrequired on the side member 15, since the dimensions of the monorail 117 are very small compared with the width of the trailer or the height of the wall panel, in contradistinction to the prior art apparatus employing track means. The carriage 19 may be supported on the monorail 17 by any suitable means that has the requisite low friction to facilitate movement of the carriage longitudinally of the monorail. As illustrated, the carriage 19 has a first set of wheels 21 and 23 bolted thereto such that the carriage 19 may traverse the monorail 17 by rolling friction in response to pressure in either direction by an operator. The wheels 21 and 23 have peripherally disposed flanges 25 that engage the monorail 17 for reasons which will become apparent from the descriptive matter later hereinafter.

A first means 27 is provided for facilitating movement of the carriage 19 longitudinally of the monorail 17 with minimal friction and aligned therewith for smooth movement therealong, for retaining the carriage 19 on the monorail 17 with sufficient force to carry a cantilevered gun 29 and for facilitating removal and installation of the carriage l9 and its gun 29 from and onto the monorail 17. The first means 27 may comprise any means which will effect the results within the limitations delineated hereinbefore. As illustrated in the figures, and most clearly in FIG. 3, the first means comprises a second rail 31 vertically spaced from the monorail 17 and a second set of at least one wheel 33. The second set, or bottom wheel 33, is disposed on and engages the side of the second rail 31 opposite monorail 17 such that the carriage can be rolled onto and from the two vertically spaced rails for easy assembly and disassembly. Specifically, the carriage 19 can be merely rolled off of the ends 35, FIG. 1, of the rails 17 and 31 and stored on a trailer or in a towing vehicle for transporting to a job site. Thereafter, the carriage 19 can be simply rolled onto the rails for use in fabricating the wall panel or the like. The bottom wheel 33 also has peripherally disposed flanges that engage the second rail 31, just as the top wheels 21 and 23 engage the top of the monorail 17. With this structure, the carriage 19 is retained in engagement with the rails with the requisite force to support the cantilevered gun 29. The two sets of spaced apart wheels; namely, the top wheels 21 and 23 and the bottom wheel 33; maintain the carriage 19 in alignment and prevent its binding as the operator pushes it longitudinally of the monorail 17. Moroever, the rolling friction of the wheels facilitate movement longitudinally of the monorail 17.

A vertically-movable support plate 37, FIGS. 1 and 2, is disposed on said carriage 19 for supporting the gun 29, its holder 39 and the fasteners, such as nails 41 in the holder. Other types of fasteners, such as T-staples or the like, can be employed where appropriate. The gun 29 will be appropriate for the particular fastener employed. The guns and fasteners are conventional and need not be described in detail herein. As illustrated, the nailing gun 29 is of the fluid pressure operated type, the pressure to fire the gun being supplied by way of hose 43, FIG. I. On the other hand, electrically fired guns may be employed, the motive power being supplied by any conventional source. As illustrated, the gun 29 is installed in a slot 45 of gun support member, referred to herein simply as gun member 47, FIG. 2. The gun is retained in slot 45 by suitable bolts 46, FIG. 1, through apertures 48, FIG. 2. The gun member 47 is connected with the support plate 37 by a substantially horizontal shaft 49 such that the gun member is pivotally mounted for limited movement in a vertical plane with respect to the support plate 37. Adjusting screws 51 allow adjusting the degree of limited movement effected by the gun member 47. The support plate 37 is movable longitudinally of a pair of guide rods 53 carried by mounting brackets 55 on carriage 19. Suitable set screws 57 retain the guide rods 53 in place. Thus, the support plate 37 may be moved vertically smoothly by either the operator or the adjustable biasing means 59.

A stop means is provided for limiting vertical movement of the support plate 37 responsive to upward biasing by the adjustable biasing means 59. Any suitable stop may be employed. As illustrated, the stop means comprises a multi-position stop 61 in which an adjustable first stop 63 may be pivoted into position, as illustrated in FIG. 2, such that the adjustable screw 65 limits upward movement of the bracket 67 supporting the support plate 37 and slideably encompassing the guide rod 53. This allows effecting an uppermost position for the gun 29 to nail the smallest width studs that will be employed; for example, to nail the top of 2 X 4 inch studs 11 to the plate 13. On the other hand, the adjustable first stop 63 may be pivoted on its shaft 69 out of the way, as by rotating outwardly and to the left in FIG. 2 to allow the brackets 67 to move upwardly into contact with the main stop of the stop means, as for nailing wider studs such as 2 X 10 inch studs. Moreover, the first stop 63 may be positioned on the top of the support bracket, with or without adjustable screw 65 to nail 2 X 6s or 2 X 8s for complete flexibility.

An adjustable biasing means 59 is provided for yieldingly urging the support plate 37 upwardly into its uppermost position in'engagement with the stop means. As indicated hereinbefore, the gun 29 and the support plate 37 are movable downwardly by an operator against the adjustable biasing means position the support plate 37 and the gun 29 in a plurality of vertically spaced nailing positions adjacent each joint. To alleviate the second major disadvantage of the prior art apparatus, it is imperative that the biasing means be adjustable. To be practical, the biasing means must be readily adjustable manually by an operator as the nails 41 or the like are used up from the holder 39. Any adjustable biasing means can be employed. For example, a resilient spring can be employed in conjunction with a nut that can be loosened to decrease the force with which the gun was biased toward its uppermost position. As illustrated, the adjustable biasing means comprises a fluid powered ram 71 and a pressure. regulator 73, FIGS. 2 and 3, connected with a source of fluid at superatmospheric pressure. The ram 71 is connected with the vertically movable support plate 37 and the carriage 19 for biasing the support plate 37 to its uppermost position. Specifically, the shaft 72 of the ram 71 engages the L shaped extension. 74 which is connected with the support plate 37, as by welding. The ram 71 comprises a pneumatic ram and the source of fluid comprises compressed air. The compressed air is also supplied by way of hose 43 for firing the gun 29 in the illustrated embodiment. The pressure regulator 73 has a manually operable means such as knob 75 for adjusting the downstream pressure supplied to ram 71. In this way, the operator can reach down to rotate the knob 75 counter clockwise to reduce the pressureand reduce the force withwhich the gun 29 is biased upwardly. Conversely, when the holder 39 is refilled and a greater force is advisable to return the gun 29 to its uppermost position, the operator may rotate the knob 75 in a clockwise direction, viewed from the top to increase the pressure supplied to the ram 71. Expressed otherwise, the pressure regulator 73 can be adjusted to increase or decrease the force to the optimum deemed most advantageous by a particular operator in view of the weight of the holder 39; and the operator can adjust trated in FIG. 2. The carriage 19 then has its top wheels 21 and 23 and its bottom wheel 33 rolled into the rails '17 and 3l. The peripheral flanges 25 of the wheels grip the rails to retain the carriage 19 on the monorail 17,-

yet can be readily rolled from the ends, as indicated hereinbefore. The gun 29 is inserted in slot 45 and bolted in place by bolts 46 through apertures 48. The conduit supplying compressed air from a source (not shown) is connected to the pressure regulator which is connected to the ram 71; and the air supply source is connected directly to the gun by hose 43. The nails 41 are emplaced in the holder 39 and the gun 29. The desired pressure downstream of the regulator is dialed by turning the knob .75. The gun is ready to be tired. The plates 11 and studs 13 are emplaced with their joints adjacent the edge. The operator then proceeds down the side nailing the top and bottom of. each joint. The gun is automatically in place for nailing the top nail of the joint but the operator must push downwardly against the pneumatic ram 71 to nail the bottom nail. As the nails are used up, the operator may lower the pressure from the regulator 73 to lessen the force against which he must move the gun 29 downwardly into the bottom nailing position. If desired the pressure regulator 73 can be a self-bleeding regulator such that it automatically lowers the pressure to the new pressure even when that is lower than the original pressure. Ordinarily, however, there is sufficient leakage of the air as the gun is moved upwardly and downwardly to the respective uppermost and lowermost positions, that there is no problem with attainingthe regulated pressure; even if it is lower than the pre-set pressure.

When the trailer is employed and is to be towed to a job site, the carriage 19 and the gun 29 may be readily rolled off the ends of the rails 17 and 31, and the trailer towed on the-highway, legally and without the wide lateral protrusions on each side.

From the foregoing descriptive matter and drawings, it can be seen that this invention provides a gun mount that obviates the disadvantages of the prior art apparatus, singly or together. The gun mount of this invention may be emplaced adjacent lineally spaced joints, regardless of whether they are emplaced on a platform or trailer or at other locations. The gun mount of this invention has met with wide commercial acceptance, in contrast to some of the prior art apparatus.

Although this invention has been described with a certain degree of particularity, it is understood that the present disclosure has been made only by way of example and that numerous changes in the details of construction and the combination and arrangement of parts may be resorted to without departing from the spirit and the scope of this invention.

I claim:

1. A semi-automatic gun mount for fastening together respective members to form a plurality of joints lineally spaced apart at a predetermined location comprising:

a. at least one rail hereinafter referred to as a monorail disposed adjacent the predetermined location, having unobstructed ends and traversing adjacent positions at which said plurality of lineally spaced joints will be formed;

b. a .carriage having top flanged wheels guideably supported on said monorail; said carriage having a minimal lateral extension of less than one foot from said positions;

c. first means including a second rail traversing parallel with said monorail and having unobstructed ends and a bottom flanged wheel disposed on the opposite side of said second rail from said carriage flanged wheels; said top and bottom flanged wheels engaging said monorail and said second rail for facilitating movement of said carriage longitudinally of said monorail with minimal friction, for retaining said carriage on said monorail with sufficientforce to carry a cantilevered gun, and being rollable onto and from the unobstructed ends thereof for facilitating removal and installation of said carriage and its gun from and onto said monorail;

its holder containing fasteners to be driven by said gun;

e. vertically movable support plate carrying said gun and its holder for fasteners;

f. two guide rods carried by said carriage and having said vertically movable support plate slidably mounted thereon for effecting smooth linear movement of said vertically movable support plate responsive to an adjustable biasing means and an operator; I

g. stop means on said carriage for limiting vertical movement of said vertically movable support plate; said stop means being multi-positionable for effecting respective top positions of said gun for fastening different size members together; and

h. adjustable biasing means for yieldinglyurging said vertically movable support plate upwardly into an uppermost position in engagement with said stop means; said vertically movable support plate being movable downwardly by an operator against said adjustable biasing means to position said vertically movable support plate and said gun in a plurality of vertically spaced nailing positions adjacent each joint; said adjustable biasing means comprising a fluid powered ram connected with said vertically movable support plate and said carriage and connected via a pressure regulator with a source of fluid at superatmospheric pressure; said pressure regulator being manually adjustable for supplying a desired force via said fluid powered ram.

2. The gun mount of claim 1 wherein said fluid comprises compressed air and said compressed air supplies the motive force for operation of both said gun and said fluid powered ram.

3. The gun mount of claim 1 wherein said gun is mounted on a gun support member that is connected with said vertically movable support plate by a substantially horizontal shaft such that said gun support member is mounted for limited pivotal movement in a vertical plane with respect to said vertically movable support plate.

4. A semi-automatic gun mount for fastening together respective members to form a plurality of joints a compressed air actuated fastener driving gun and lineally spaced apart at a predetermined location comprising:

a. track means disposed adjacent the predetermined location and traversing adjacent positions at which said plurality of lineally spaced joints will be formed;,.

b. a carriage guideably supported on said track means;

c. a compressed air actuated fastener driving gun and holder containing fasteners to be driven by said d. a vertically movable support plate disposed on said carriage and carrying said gun and said holder;

e. stop means on said carriage for limiting vertical movement of said vertically movable support plate; and

f. adjustable biasing means comprising a fluid powered ram connected with said vertically movable support plate and said carriage for yieldingly urging said vertically movable support plate upwardly into an uppermost position in engagement with said stop means; said vertically movable support plate being movable downwardly by an operator against said adjustable biasing means to position said vertically movable support plate and gun in a plurality of vertically spaced nailing positions adjacent each joint; said fluid powered ram being connected via a pressure regulator with a source of fluid at superatmospheric pressure; said pressure regulator being manually adjustable for supplying a desired force via said fluid powered ram and having readily accessible to said operator a manually operable means for readily adjusting the force with which said biasing means biases said vertically movable support plate and gun towards said stop means such that said operator can lessen said force as the weight of said holder decreases as fasteners are used therefrom; said fluid powered ram and said pressure regulator being adapted to supply said desired force against downward movement by said operator and to allow downward depression of said gun against said desired force.

5. The gun mount of claim 4 wherein at least two guide rods are mounted on said carriage and carry said vertically movable support plate for effecting smooth linear movement of said vertically movable support plate responsive to said adjustable biasing means and said operator; said stop means is multi-positionable for effecting respective top positions of said gun for fastening different sized members together.

6. The gun mount of claim 4 wherein said fluid comprises compressed air and said compressed air supplies the motive force for operation of both said gun and said fluid powered ram.

7. A semi-automatic gun mount for fastening together respective members to form a plurality of joints lineally spaced apart at a predetermined location com prising:

a. track means disposed adjacent the predetermined location and traversing adjacent positions at which said plurality of lineally spaced joints will be formed;

b. a carriage guideably supported on said track means;

0, a fastener driving gun and holder containing fasteners to be driven by said gun;

d. a vertically movable support plate disposed on said carriage and carrying said gun and said holder; said gun being installed on said vertically movable support plate by being mounted on a gun support member that is connected with said vertically movable support plate by a substantially horizontal shaft, such that said gun support member is mounted for limited pivotal movement in a vertical plane with respect to said vertically movable support plate;

e. stop means on said carriage for limiting vertical movement of said vertically movable support plate;

and

adjustable biasing means for yieldingly urging said vertically movable support plate upwardly into an uppermost position in engagement with said stop means; said vertically movable support plate being movable downwardly by an operator against said adjustable biasing means to position said vertically movable support plate and gun in a plurality of vertically spaced nailing positions adjacent each joint; said adjustable biasing means having readily accessible to said operator a manually operable means for adjusting the force with which said biasing means biases said vertically movable support plate and gun toward said stop means such that said operator can lessen said force as the weight of said holder decreases as fasteners are used therefrom.

8. A semi-automatic gun mount for fastening together respective members to form a plurality of joints lineally spaced apart at a predetermined location comprising:

a. a side support traversing adjacent the spaced apart joints at said predetermined location;

b. a monorail disposed adjacent the predetermined location and traversing adjacent positions at which said plurality of lineally spaced joints will be formed; said monorail being fastened to said side support at a plurality of locations disposed periodically along its length and having one side and ends unobstructed;

c. a carriage guideably supported on said monorail with minimal lateral extension of less than 1 foot from said positions; said carriage having a set of at least one cantilevered wheel having peripheral flanges engaging said monorail such that said set of at least one wheel is adapted to traverse the full length of said monorail and to be rolled thereonto and therefrom to facilitate assembly for work and disassembly for storage or transportation;

d. first means comprising a second rail fastened to said side support, traversing parallel with said monorail and having one side and ends unobstructed, and a second set of at least one cantilevered, peripherally flanged wheel engaging said second rail on the opposite side from said first set of said at least one wheel on said carriage such that said second set of at least one wheel is adapted to traverse the full length of said second tail for facilitating movement of said carriage longitudinally of said monorail with minimal friction, for retaining said carriage on said monorail with sufficient force to carry a cantilevered gun, and to be rolled thereonto and therefrom for facilitating removal and installation of said carriage and its gun from and onto said monorail and said second rail to facilitate as- 9 10 sembly for Work and disassembly for storage or h. biasing means for yieldingly uring said vertically transportation as noted in element c.; movable support plate upwardly into an uppermost e. a fastener driving gun and its holder containing fasposition in engagement with said stop means; said teners to be driven by said gun; support plate being movable downwardly by an opf. vertically movable support plate disposed on said 5 erator against said biasing means to position said carriage and supporting said gun and holder; vertically movable support plate and said 'gun in ag. stop means on said carriage for limiting vertical plurality of vertically spaced nailing positions adjamovement of said vertically movable support plate; cent each joint. and 

1. A semi-automatic gun mount for fastening together respective members to form a plurality of joints lineally spaced apart at a predetermined location comprising: a. at least one rail hereinafter referred to as a monorail disposed adjacent the predetermined location, having unobstructed ends and traversing adjacent positions at which said plurality of lineally spaced joints will be formed; b. a carriage having top flanged wheels guideably supported on said monorail; said carriage having a minimal lateral extension of less than one foot from said positions; c. first means including a second rail traversing parallel with said monorail and having unobstructed ends and a bottom flanged wheel disposed on the opposite side of said second rail from said carriage flanged wheels; said top and bottom flanged wheels engaging said monorail and said second rail for facilitating movement of said carriage longitudinally of said monorail with minimal friction, for retaining said carriage on said monorail with sufficient force to carry a cantilevered gun, and being rollable onto and from the unobstructed ends thereof for facilitating removal and installation of said carriage and its gun from and onto said monorail; d. a compressed aiR actuated fastener driving gun and its holder containing fasteners to be driven by said gun; e. vertically movable support plate carrying said gun and its holder for fasteners; f. two guide rods carried by said carriage and having said vertically movable support plate slidably mounted thereon for effecting smooth linear movement of said vertically movable support plate responsive to an adjustable biasing means and an operator; g. stop means on said carriage for limiting vertical movement of said vertically movable support plate; said stop means being multi-positionable for effecting respective top positions of said gun for fastening different size members together; and h. adjustable biasing means for yieldingly urging said vertically movable support plate upwardly into an uppermost position in engagement with said stop means; said vertically movable support plate being movable downwardly by an operator against said adjustable biasing means to position said vertically movable support plate and said gun in a plurality of vertically spaced nailing positions adjacent each joint; said adjustable biasing means comprising a fluid powered ram connected with said vertically movable support plate and said carriage and connected via a pressure regulator with a source of fluid at superatmospheric pressure; said pressure regulator being manually adjustable for supplying a desired force via said fluid powered ram.
 2. The gun mount of claim 1 wherein said fluid comprises compressed air and said compressed air supplies the motive force for operation of both said gun and said fluid powered ram.
 3. The gun mount of claim 1 wherein said gun is mounted on a gun support member that is connected with said vertically movable support plate by a substantially horizontal shaft such that said gun support member is mounted for limited pivotal movement in a vertical plane with respect to said vertically movable support plate.
 4. A semi-automatic gun mount for fastening together respective members to form a plurality of joints lineally spaced apart at a predetermined location comprising: a. track means disposed adjacent the predetermined location and traversing adjacent positions at which said plurality of lineally spaced joints will be formed; b. a carriage guideably supported on said track means; c. a compressed air actuated fastener driving gun and holder containing fasteners to be driven by said gun; d. a vertically movable support plate disposed on said carriage and carrying said gun and said holder; e. stop means on said carriage for limiting vertical movement of said vertically movable support plate; and f. adjustable biasing means comprising a fluid powered ram connected with said vertically movable support plate and said carriage for yieldingly urging said vertically movable support plate upwardly into an uppermost position in engagement with said stop means; said vertically movable support plate being movable downwardly by an operator against said adjustable biasing means to position said vertically movable support plate and gun in a plurality of vertically spaced nailing positions adjacent each joint; said fluid powered ram being connected via a pressure regulator with a source of fluid at superatmospheric pressure; said pressure regulator being manually adjustable for supplying a desired force via said fluid powered ram and having readily accessible to said operator a manually operable means for readily adjusting the force with which said biasing means biases said vertically movable support plate and gun towards said stop means such that said operator can lessen said force as the weight of said holder decreases as fasteners are used therefrom; said fluid powered ram and said pressure regulator being adapted to supply said desired force against downward movement by said operator and to allow downward depression of said gun against said desired force.
 5. The gun mount of claim 4 wherein at least two guide rods are mounted on said caRriage and carry said vertically movable support plate for effecting smooth linear movement of said vertically movable support plate responsive to said adjustable biasing means and said operator; said stop means is multi-positionable for effecting respective top positions of said gun for fastening different sized members together.
 6. The gun mount of claim 4 wherein said fluid comprises compressed air and said compressed air supplies the motive force for operation of both said gun and said fluid powered ram.
 7. A semi-automatic gun mount for fastening together respective members to form a plurality of joints lineally spaced apart at a predetermined location comprising: a. track means disposed adjacent the predetermined location and traversing adjacent positions at which said plurality of lineally spaced joints will be formed; b. a carriage guideably supported on said track means; c. a fastener driving gun and holder containing fasteners to be driven by said gun; d. a vertically movable support plate disposed on said carriage and carrying said gun and said holder; said gun being installed on said vertically movable support plate by being mounted on a gun support member that is connected with said vertically movable support plate by a substantially horizontal shaft, such that said gun support member is mounted for limited pivotal movement in a vertical plane with respect to said vertically movable support plate; e. stop means on said carriage for limiting vertical movement of said vertically movable support plate; and f. adjustable biasing means for yieldingly urging said vertically movable support plate upwardly into an uppermost position in engagement with said stop means; said vertically movable support plate being movable downwardly by an operator against said adjustable biasing means to position said vertically movable support plate and gun in a plurality of vertically spaced nailing positions adjacent each joint; said adjustable biasing means having readily accessible to said operator a manually operable means for adjusting the force with which said biasing means biases said vertically movable support plate and gun toward said stop means such that said operator can lessen said force as the weight of said holder decreases as fasteners are used therefrom.
 8. A semi-automatic gun mount for fastening together respective members to form a plurality of joints lineally spaced apart at a predetermined location comprising: a. a side support traversing adjacent the spaced apart joints at said predetermined location; b. a monorail disposed adjacent the predetermined location and traversing adjacent positions at which said plurality of lineally spaced joints will be formed; said monorail being fastened to said side support at a plurality of locations disposed periodically along its length and having one side and ends unobstructed; c. a carriage guideably supported on said monorail with minimal lateral extension of less than 1 foot from said positions; said carriage having a set of at least one cantilevered wheel having peripheral flanges engaging said monorail such that said set of at least one wheel is adapted to traverse the full length of said monorail and to be rolled thereonto and therefrom to facilitate assembly for work and disassembly for storage or transportation; d. first means comprising a second rail fastened to said side support, traversing parallel with said monorail and having one side and ends unobstructed, and a second set of at least one cantilevered, peripherally flanged wheel engaging said second rail on the opposite side from said first set of said at least one wheel on said carriage such that said second set of at least one wheel is adapted to traverse the full length of said second rail for facilitating movement of said carriage longitudinally of said monorail with minimal friction, for retaining said carriage on said monorail with sufficient force to carry a cantilevered gun, and to be rolled thEreonto and therefrom for facilitating removal and installation of said carriage and its gun from and onto said monorail and said second rail to facilitate assembly for work and disassembly for storage or transportation as noted in element c.; e. a fastener driving gun and its holder containing fasteners to be driven by said gun; f. vertically movable support plate disposed on said carriage and supporting said gun and holder; g. stop means on said carriage for limiting vertical movement of said vertically movable support plate; and h. biasing means for yieldingly uring said vertically movable support plate upwardly into an uppermost position in engagement with said stop means; said support plate being movable downwardly by an operator against said biasing means to position said vertically movable support plate and said gun in a plurality of vertically spaced nailing positions adjacent each joint. 